جستجوی مقالات مرتبط با کلیدواژه « نوع خاک » در نشریات گروه « آب و خاک »

Kerman province with mean annual precipitation about 130 mm is categorized among dry provinces.Then producing the maximum agricultural products using minimum water consumption is highly important increasing soil water content and preventing of water deep.Percolation is one of the best ways to use water more efficiently in agricultural practices. In this regard using super absorbent gel is one of the newest methods that. Some studies have been carried on it.In a greenhouse test the effect of soil type , percent of soil moisture content and the amount of super absorbent in a purely random test of factorial with three factors : soil type ( heavy or light ) , percent soil moisture and the amount of super absorbent ( 0 , 100 , 200 , 400 , 800 , kg/ha ) , the effect of them evaluated on the height of maize , and surface of plant . The effect of soil type.  Percent of soil moisture and the amount of super absorbent showed significant difference on plant height and inflammation of leaf.The best results on growing factor of the plant achieved by using 400 kg of s.j in light soil with 60 % of soil water content.

Crop coefficient varies in different environmental conditions, such as deficit irrigation, salinity and intercropping. The effect of soil fertility and texture of crop coefficient and evapotranspiration of maize was investigated in this study. Low soil fertility and food shortages as a stressful environment for plants that makes it different evapotranspiration rates of evapotranspiration calculation is based on the FAO publication 56. Razzaghi et al. (2012) investigate the effect of soil type and soil-drying during the seed-filling phase on N-uptake, yield and water use, a Danish-bred cultivar (CV. Titicaca) was grown in field lysimeters with sand, sandy loam and sandy clay loam soil. Zhang et al (2014) were investigated the Effect of adding different amounts of nitrogen during three years (from 2010 to 2012) on water use efficiency and crop evapotranspiration two varieties of winter wheat. The results of their study showed. The results indicated the following: (1) in this dry land farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2) N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3) comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.
The study was a factorial experiment in a completely randomized design with three soil texture treatment, including silty clay loam, loam and sandy-loam soil and three fertility treatment, including without fertilizer, one and two percent fertilizer( It was conducted at the experimental farm in Jey and Qahab district of Isfahan. Reference evapotranspiration and actual evapotranspiration of maize were measured by evaporation pan method and volumetric soil water balance method using micro lysimeters, respectively. In order to accommodate the growing field conditions, a ditch with a depth of 25 cm, length of 240 cm and width of 300 cm were dug and micro-lysimeters were placed it in three rows (three replications) with a distance of 75 cm. After preparing the treatments, four seed Maize with variety of NS540 were planted at a depth of 3-5 cm on 5 August. To reduce the oasis effect on evapotranspiration, the same corn was planted in the vicinity of the project area with 500 square meters..
The results showed that using fertilizer caused increasing of crop evapotranspiration and crop coefficient of maize. Maximum of the ten-day average evapotranspiration of maize in the silty clay loam soil with two percent fertilizer was obtained 8.76 (mm/ day) on the fifth decade of growth and this value was found 45.5 percent higher than the lowest mean evapotranspiration value of the ten-day. Comparison evapotranspiration of maize in different soil fertility treatments showed that the greatest impact on increasing of maize evapotranspiration in SLF2, SCLF2, SLF2 treatments were obtained that was equal %19.1, %14.3 and %10.6, respectively (table 4). Most of the effects of fertility the crop coefficient of maize at the middle stage of growth was influenced more than other stages by the different treatments of soil fertility. Adding one and two percent of the fertilizer to treatment SCLF0 increased maize crop coefficient about 3.5 and 9.7 percent at development stage, respectively, That measured %6 and 11% for LF1 and LF2 treatments, respectively, and about 1.6 and 5.6% for SLF2 SLF1 treatment, respectively (Table 6). Comparison of maize middle crop coefficient in SLF2 and SLF1 for different soil fertility treatments showed that effect of increasing soil fertility on middle Kc of maize was more than other stages of plant growth (Table 6). The obtained results showed that the addition of one and two percent fertilizer to the silty clay loam soil increased, the middle crop coefficient 13.3% and 27%, respectively in.
Maximum and minimum effect of soil fertility on increasing crop coefficient of maize in the middle stage was equal to 37.8% in the loamy soil and 18.3% in the sandy loam soil with two percent fertilizer. The greatest effect of soil fertility on crop coefficient of maize was measured 8.37% in the middle stage of growth in LF2. The effect of soil fertility on crop coefficient of maize in loam and silty clay loam soils more than sandy loam soil, Because can be a further organic matter in these soils (loam and silty clay loam and also decreasing evaporation in sandy loam soil.

Determination of crops water requirement in different environmental conditions is essential for preparation of precise and suitable irrigation scheduling. The effect of soil compaction and texture on crop coefficient and evapotranspiration of maize was investigated in this study, which was conducted as a factorial experiment with a completely randomized design in a research farm in Jey and Qahab district in Isfahan. The study included three soil texture treatments of silty clay loam, loam, and sandy loam, and three compaction treatments including natural density of field soils, compaction by dropping 2.5 kg weights 25 and 50 times (based on the standard Proctor test). In order to determine the reference evapotranspiration of maize, evaporation pan method was used, and for actual evapotranspiration, volumetric soil water balance method was adopted by using micro-lysimeters-drains (32 cm diameter and 80 cm height). The results showed that by increasing soil compaction crop evapotranspiration and crop coefficient of maize were reduced at the different growth stages. The maximum 10-day average evapotranspiration of maize was obtained at 8.76 mm/day in silty clay loam soil with natural bulk density of 1.27 g/cm3. This value was 70 percent higher than the minimum 10-day average evapotranspiration in the fifth decade of growth. Increasing the soil bulk density decreased total crop evapotranspiration 23%, 20.8%, and 12.8% in loam, silty clay loam, and sandy loam soil, respectively. The maximum and minimum impact of soil bulk density on crop coefficient of maize was observed in the middle and initial growth stages, respectively. The maximum and minimum impact of increased soil bulk density on reduction of crop coefficient of maize in the middle growth stage was 40.3% in loam soil and 20.7% in sandy loam soil for the second bulk density treatment.